1. Field of the Invention
The present invention relates to an attachment for the replacement of an ink ribbon contained in an ink ribbon cassette, as well as an ink ribbon cassette suitable for the replacement of an ink ribbon using said attachment.
2. Description of the Related Art
The ink ribbon cassette referred to above has an ink ribbon accommodated in the interior thereof and it is put onto a printer such as a thermal printer or a dot printer to effect printing.
The thermal printer is generally constructed as follows.
In the thermal printer with its top cover opened, a flat plate like-platen is disposed nearly centrally of a frame in the interior thereof in such a manner that a printing surface thereof faces substantially in the vertical direction. In front of the platen and in a lower position there is disposed a carriage in parallel with the platen. Further, at the front edge of the above frame there is formed a flange-like guide portion, and the carriage is in engagement with the carriage shaft and the guide portion so that it can reciprocate along the carriage shaft and the guide portion.
A thermal head is attached to the front end portion of the carriage so as to be opposed to the platen. On the carriage are disposed a take-up reel driving shaft adapted to fit in a take-up reel of an ink ribbon cassette to rotate the reel, and a feed reel guide shaft for guiding a feed reel of the ink ribbon cassette rotatably. The ink ribbon cassette, in which an ink ribbon is contained and is guided to the position between the thermal head and the platen, is loaded onto the carriage removably.
When the ink ribbon contained in the conventional ink ribbon cassette for the thermal printer has been consumed completely, the cassette case can be re-used by the replacement of only the ink ribbon.
In the conventional ink ribbon cassette, however, the whole of the cassette case with ink ribbon is in many cases discarded without making ribbon replacement because the cassette case opening operation by releasing the engagement of a retaining member which is for holding upper and lower cassette cases as constituents of an ink ribbon cassette body integrally with each other, and the handling of a ribbon feed roller supported within the ink ribbon cassette, are troublesome.
However, in the recent clamor for resources saving, it has become necessary to simplify the replacement work for ink ribbon alone with a view to making the most of an employable member.